package com.xiaoxu.bbs.filter;

import com.alibaba.fastjson.JSON;
import com.xiaoxu.bbs.common.BaseContext;
import com.xiaoxu.bbs.common.ReturnResults;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@Slf4j
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器（可支持通配符）
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        log.info("拦截到请求: {}",request.getRequestURI());

//        if(true) {
//            filterChain.doFilter(request, response);
//            return;
//        }

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/user/login",
                "/user/logout",
                "/user/register",
                "/common/upload",
                "/common/download",
                "/static/**",
        };
        //1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        //2.判断本次请求是否需要处理
        boolean match = check(urls,requestURI);
        //3.如果不需要处理，则直接放行
        if (match){
            filterChain.doFilter(request,response);
            return;
        }
        //4.判断登录状态，如果已经登录，则直接放行
        Long userId = (Long) request.getSession().getAttribute("user");
        if (userId != null){
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request,response);
            return;
        }
        //5.如果未登录则返回未登录结果
        response.getWriter().write(JSON.toJSONString(ReturnResults.error("NOTLOGIN")));
    }

    /**
     * 路径匹配，判断请求是否需要处理
     */
    public boolean check(String[] urls,String requestURI){
        for (String url:urls) {
            boolean match = PATH_MATCHER.match(url,requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
